Current, Voltage & Ammeters Flashcards
What is a current
The amount of charge flowing per second
What units is current measured in
Amps
What equipment can you use to measure current
Ammeters
How can a loop of string be used to model a current
Rope presents the charges and the amount of rope moving per second is the current
What is the job of a cell / battery in a circuit
They push charges around the circuit
State some examples of circuit components
Bulb
Buzzer
Motor
Resistor
What is meant by potential difference
The push that makes a charge move around a circuit
What unit is potential difference measured in
Volts
What equipment can be used to measure potential difference
Voltmeter
How do you measure the potential difference of a power supply
Connect the voltmeter around the battery
How do you measure the potential difference of a component
Connect the voltmeter around the component
What happens to the potential difference in a series circuit
Total potential difference of components equals the potential difference of the power supply
What happens to the potential difference in a parallel circuit
The potential difference is the same across each loop
What happens to the current in a series circuit
It is the same all the way around the circuit
What happens to the current in a parallel circuit
It splits up at the junction
What is the difference between a series and a parallel circuit
A series has one loop whereas a parallel has more than one loop
How could you represent a parallel circuit using a model
Hold more than one loop of rope so the battery moves at the same time
What does a resistor do
It slows down the current
What is resistance
How easy or hard it is to let the current through
What is resistance measured in
Ohms
What equation can be used to calculate resistance
Resistance = Potential Difference ÷Current
What do the Electrons do ad they move through a wire
They collide with the atoms
What does Elctrons moving through wires cause
It causes the wire to heat up and the Electrons lose energy
What is meant by an electrical conductor
Something that has low resistance and let’s a lot of electricity through easily
